New GL-4 Oil
- Thread starter glxpassat
- Start date
Good on them. John Deere Hygard has carried the spec for years. That’s one of the reasons I felt comfortable using it in my M5OD transmission in my Ranger. Have also used it in a C6 auto with slightly firmer shifts than atf.
- Joined
- Jun 13, 2013
- Messages
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I wonder what the viscosity is?
Full synthetic?
90W gear oil?
Full synthetic?
90W gear oil?
I'm pretty sure its made by Mag1, and their product is analogous to Supertech. See the viscosity below:
https://mag1.com/products/transmiss...ag-1-universal-tractor-trans-hydraulic-fluid/
looks like 9.3 cst @100C, or 80 weight gear oil. 1300 ppm Phos and 3340 ppm Calcium in that oil.
- Joined
- Jun 13, 2013
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Looks a little thin to be GL-4
I will stick with Caterpillar Final Drive 50…
I will stick with Caterpillar Final Drive 50…
MolaKule
Staff member
GL-4 dedicated Manual Transmission fluids come in viscosities ranging from 6 cSt@100C to 21 cSt@100C. Again, the GL rating is a "protection/wear" rating and has nothing to do with viscosity.
I'm intrigued by this. IE, if two fluids have GL-4 rating, but are much different viscosity, will they offer the same wear protection just at different cost and cold weather shift performance? Intuitively it seems making a 75w-90 GL-4 could cost much less (using lower grade fluid with fewer additives) than a 0w-30 GL-4, but are they interchangable in the same application as far as protection goes since they both are GL-4 rated?
In a real-world scenario? No, it won't provide the same protection. Film thickness depends on viscosity.
If it were different I'd run a 70W-75 or 75W in any of my cars.
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If it were different I'd run a 70W-75 or 75W in any of my cars.
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MolaKule
Staff member
A number of different topics are raised here but the answers will only apply to dedicated or "application-specific" MTFs.
1) For manual transmissions only dedicated or "application-specific" manual transmission fluids (MTF) offering GL-4 ratings should be used in passenger vehicle and light truck transmissions. Over-the-road or HD truck transmissions are not part of this discussion. Gone is the day when engine oils are to be used.
2) One cannot assume any GL-4 lubricant will offer the proper wear protection and friction modification, only dedicated or "application-specific" MTFs will do that. See for example the Redline, Amsoil, and foreign blender line ups of MTFs.
3) The wear protection chemistry, and in fact the overall DI additive chemistry package is primarily the same over all viscosity offerings or ranges, so yes, the same wear protection is present.
4) It is not a matter of more or less additives as to cost, but the proper mix of additives. Engine oil DI additives involve a totally different type of additive chemistry and a different mix of base oils than do MTFs.
5) The GL-4 rating has NO relationship to viscosity., and it seems this is still widely misunderstood and propagated on the internet.
6) Why do most passenger vehicle and light truck transmission manf. specify a GL-4 wear/protection rating? It is because of the level of torque transmitted through the transmission and the internal loading, the internal forces expected on the bearings and the gear teeth, the gearing design, and the reaction forces encountered.
7) As to interchangeability I am not clear what you are asking. My canned response to the replacement of OEM fluids with AfterMarket fluid offerings is this: Before you order ANY MTF for a drain and fill, take a sample of the OEM fluid from the transmission and have it analyzed. Post the analysis here
Gear & Transmission Used/Virgin Oil Analysis
Virgin and Used Gear & Transmission Analysis reports.
bobistheoilguy.com
with the mileage currently on the MTF and transmission. The resulting report on its viscosity and the general chemical signature will give us a clue as to which AfterMarket fluid offering will best fit your application (your specific transmission and driving conditions).
All good questions!
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Thanks so much Molakule! By interchangeabiltiy, I mean, if my old Nissan truck specs a 75w-90 GL-4 and I put in a 70w-80 GL-4, am I creating a condition where more wear will occur. Or since they are both GL-4, should the same amount of wear occur reguardless of viscosity? Companies like Redline offer both examples, so I'm not sure why anyone would choose the thicker fluid which creates harder shifts in the cold...if they offer the same wear protection...A number of different topics are raised here but the answers will only apply to dedicated or "application-specific" MTFs.
1) For manual transmissions only dedicated or "application-specific" manual transmission fluids (MTF) offering GL-4 ratings should be used in passenger vehicle and light truck transmissions. Over-the-road or HD truck transmissions are not part of this discussion. Gone is the day when engine oils are to be used.
2) One cannot assume any GL-4 lubricant will offer the proper wear protection and friction modification, only dedicated or "application-specific" MTFs will do that. See for example the Redline, Amsoil, and foreign blender line ups of MTFs.
3) The wear protection chemistry, and in fact the overall DI additive chemistry package is primarily the same over all viscosity offerings or ranges, so yes, the same wear protection is present.
4) It is not a matter of more or less additives as to cost, but the proper mix of additives. Engine oil DI additives involve a totally different type of additive chemistry and a different mix of base oils than do MTFs.
5) The GL-4 rating has NO relationship to viscosity., and it seems this is still widely misunderstood and propagated on the internet.
6) Why do most passenger vehicle and light truck transmission manf. specify a GL-4 wear/protection rating? It is because of the level of torque transmitted through the transmission and the internal loading, the internal forces expected on the bearings and the gear teeth, the gearing design, and the reaction forces encountered.
7) As to interchangeability I am not clear what you are asking. My canned response to the replacement of OEM fluids with AfterMarket fluid offerings is this: Before you order ANY MTF for a drain and fill, take a sample of the OEM fluid from the transmission and have it analyzed. Post the analysis here
Gear & Transmission Used/Virgin Oil Analysis
Virgin and Used Gear & Transmission Analysis reports.bobistheoilguy.com
with the mileage currently on the MTF and transmission. The resulting report on its viscosity and the general chemical signature will give us a clue as to which AfterMarket fluid offering will best fit your application (your specific transmission and driving conditions).
All good questions!
MolaKule
Staff member
One of the reasons for the varying viscosity offerings has to do with shifter fork forces verses viscosity at temperature, i.e., shifting forces at various temperatures.
Of course, manf. also specify the viscosity or the viscosity grade according to the minimum film thickness they allow in the parts clearances, so it is a delicate balancing act to specify a fluid with low temperature shiftability and minimum oil film thickness for at least 100C.
You could be creating more wear since the oil films between the gearing and bearings would be thinner. Let the fluid warm up on cold mornings before driving.
Some have reported no real increase in overall wear and better cold weather shifting by going from say from MT-90 to MT-85.
Of course, manf. also specify the viscosity or the viscosity grade according to the minimum film thickness they allow in the parts clearances, so it is a delicate balancing act to specify a fluid with low temperature shiftability and minimum oil film thickness for at least 100C.
glxpassat said:
You could be creating more wear since the oil films between the gearing and bearings would be thinner. Let the fluid warm up on cold mornings before driving.
Some have reported no real increase in overall wear and better cold weather shifting by going from say from MT-90 to MT-85.
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My case is i have a car, well both my cars in fact recommend Monograde SAE 80W GL-4 gear oils for their gearboxes.
Up until recently i was still able to locally source one Castrol made which i currently have in both and works just fine, but i like changing MTF's at 5 year intervals maximum, thankfully on both it's possible as they have drain and fill plugs.
But i am looking at what to use next, i've been looking at 75W-80 but most have a somewhat thinner Kv100 than the 80 Mono and the Kv40 on all of them seems way lower and i am worried they may cause problems, what do you think?
Then also the Capri requires an EP90 Hypoid oil for the diff, which is also hard to find, i've been looking at 80W-90 or 85W-90 for the next change.
Redline is a bit out of the question, here in Spain it's just too expensive to justify.
MolaKule
Staff member
What are the actual viscosities of this 80W?
Here you have it
Attachments
Lower KV40 is never gonna be an issue (as cold oil is thick anyway). Lower KV100 potentially is.
With KV100 at 9.9 mm²/s(cSt) you could easily replace Castrol Manual EP80 with a synthetic GL-4 75W-85 or 75W-90. Castrol Syntrans Multivehicle 75W-90 GL-4 comes to mind. There's also a 75W-85 brother but it isn't available in 1 l bottles. Both are thinner at 40°C (and more so below), though thicker at 100°C. At operating temp most of the time they're likely similar in viscosity to Castrol Manual EP80. Castrol Syntrans Multivehicle 75W-90 GL-4 is fairly comparable to Redline MT90 in base oil quality but much cheaper in Europe.
That factory recommendation is almost 50 years old. Take it with a grain of salt.
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MolaKule
Staff member
If that is the case then Pennzoil Synchromesh or Valvoline Synchromesh can be used.
Here is a listing of potential candidates:
Mopar Type MS-9417 MTL 9.0 cSt
Pennzoil Synchromesh 9.5 cSt
RAVENOL SSG 9.5 cSt
Redline MTL 75W80
Amsoil MTF (9.7 cSt)
GM Synchromesh’s
Volvo MTF 645
Fuchs TITAN SINTOFLUID SAE 75W-80 synthetic MTF (Carries a GL-5 rating as well)
Lodexol (Morris Lubricants) MTF
Motylgear 75W-80
